@frisch11 I have the same problem today! Can you tell me what you deleted? I removed the BP plugin, deleted all tables in the DB related to wp_bp and also wp_bb (forums). Removed the avatar folder in uploads for images but I still have the same problem ;(

My problem is 100% the same as yours. Everything is set, upload and crop works fine but the image isn’t included in the HTML to appear.

I had the same issue, and I resolved it without deleting files and database.

To show group avatar, Buddypress uses a setting from wordpress. When it is disabled, Buddypress won’t show your group avatar. So, in admin, go to Settings > Discussion and make sure Show avatars is checked in Avatars section (you can find it at the bottom of the page).

Once I checked it, avatars started to show on my site. I hope it will be the same for you.